790 research outputs found
Demonstration of enzymatic activity converting azathioprine to 6-mercaptopurine
The enzymatic conversion of azathioprine to 6-mercaptopurine was detected at pH 6.5 with rat liver supernatants, although the non-enzymatic reaction predominated at pH 7.0 and 7.5. Glutathione S-transferase may catalize this conversion. Activities of the enzyme in liver with both zathioprine and 1,2-dichloro-4-nitrobenzene as substrate decreased upon carbon tetrachloride-induced hepatic injury. These results may explain an ineffectiveness of azathioprine in patients with severe hepatic damage.</p
Ettingshausen and Nernst effects in mixed state of YBa_2Cu_3O_<7-δ>(High Field Superconductors)
The dissipative behaviors under the Lorentz force and the thermal force are investigated for the same sample of QMG-YBa_2Cu_3O_ by measuring the Ettingshausen and the Nernst effects, respectively, and compared with each other. The value of S_φ(T) obtained from the Nernst effect is found to be smaller than that obtained from the Ettingshausen effect, which suggests that the viscosity is not the same for the vortex motions under the Lorentz force and the thermal force. The QMG-YBa_2Cu_3O_ always includes precipitates of Y_2BaCuO_5 phase which are finely dispersed by an addition of Pt. In order to investigate the effect of Y_2BaCuO_5 phase on the vortex motion, the Ettingshausen effect is also measured for the sample with 0.5 mass% Pt addition. The anisotropy of the dissipation under the thermal force is investigated by measuring the Nernst effect for the configurations; (1) H//c, (dT/dx)//ab, (2) H//ab, (dT/dr)//ab and (3) H//ab, (dT/dr)//c. For these vortex motions, viscosities are found to be in the ratio 30 : 1 : 100. The velocity of vortices is estimated from the Nernst field. Furthermore, using S_φ(T) the magnitude of viscosity is estimated to be 0.5-3×10^ N s/m^2 in the temperature range from 90 to 75 K and the magnetic field of 13 T parallel to the c-axis
Observation of Hilbert differential image by x-ray microscope andits application to phase tomography
科学研究費助成事業(科学研究費補助金)研究成果報告書:基盤研究(C)2010-2012課題番号:2261100
Pseudogap Phase Boundary in Overdoped Bi_2Sr_2CaCu_2O_8 Studied by Measuring Out-of-plane Resistivity under the Magnetic Fields
The characteristic pseudogap temperature T* in Bi2Sr2CaCu2O8 system has been
systematically evaluated as a function of doping, especially focusing on its
overdoped region, by measuring the out-of-plane resistivity under the magnetic
fields. Overdoped samples have been prepared by annealing TSFZ-grown
Bi2Sr2CaCu2O8 single crystals under the high oxygen pressures (990 kgf/cm2). At
a zero field, the out-of-plane resistivity showed a metallic behavior down to
Tc (= 62 K), while under the magnetic fields of over 3 T,it showed typical
upturn behavior from around 65 K upon decreasing temperature. This result
suggests that the pseudogap and superconductivity are different phenomena.Comment: 2 pages, 2 figures. Final version accepted for the Proceedings of the
M2S-IX Conference (Tokyo, September 2009
Eigenvalue analysis of three-state quantum walks with general coin matrices
Mathematical analysis on the existence of eigenvalues is vital, as it
corresponds to the occurrence of localization, an exceptionally important
property of quantum walks. Previous studies have demonstrated that eigenvalue
analysis utilizing the transfer matrix proves beneficial for space
inhomogeneous three-state quantum walks with a specific class of coin matrices,
including Grover matrices. In this research, we turn our attention to the
transfer matrix of three-state quantum walks with a general coin matrix.
Building upon previous research methodologies, we dive deeper into
investigating the properties of the transfer matrix and employ numerical
analysis to derive eigenvalues for models that were previously unanalyzable
Decreased Disappearance Rate of 1-(2-Tetrahydrofuryl)-5-Fluorouracil (FT-207) from the Blood and its Unresponsiveness to Tocopheryl Nicotinate and Indomethacin in Patients with Primary Hepatocellular Carcinoma
The disappearance rates(K) of FT-207 from the blood in patients with primary hepatoma and advanced cirrhosis of the liver were significantly lower than those in control patients with cancer but normal liver function. Pretreatment with tocopheryl nicotinate and indomethacin increased the K values in the control subjects, but was without effect on the K values in patients with primary hepatoma.</p
The flipped orbit of KELT-19Ab inferred from the symmetric TESS transit light curves
Dozens of planets are now discovered with large orbital obliquity, and have
become the proof for the dynamical evolution of planetary orbits. In the
current samples, there is an apparent clustering of planets around ,
and also an absence of planets around although the latter is
expected by some theories. Statistical extrapolation using Hierarchical
Bayesian Analysis have recently refuted the significant clustering around
and suggested that the distribution may actually be broader. In this
work, the symmetric TESS transit light curve of KELT-19Ab is analyzed using
gravity darkening to measure its true obliquity. Its large sky projected
obliquity makes KELT-19Ab
the only currently known planet with obliquity potentially close to
. We apply spectroscopic constraints on and
as well as theoretical constraints on the limb-darkening coefficients
to find that the KELT-19Ab's obliquity is , in favor of a flipped orbit. The result
is consistent with the statistically inferred uniformity of obliquity
distribution, and also highlights the applicability of the gravity darkening
technique to symmetric light curves.Comment: 12 pages, 6 figures. Accepted for publication in MNRA
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